A variety of electronic methods for obtaining a tremolo effect have been proposed. A number of mechanical tremolos have been available with the emphasis in improving mechanical characteristics of the device.
U.S. Patent Application Publication No. 2004/0163529 by Hyakutake et al dated Aug. 26, 2004 discloses an electronic musical instrument which can realize a choking effect by a simple operation. The electronic musical instrument is constructed such that a neck provided with a fingerboard is fixed to a body. A plurality of fret operating elements are provided for each of six sounding channels. The body is provided with a string input section and an arm, and six stringed operating elements are provided for the respective sounding channels. For each sounding channel a tone generator generates a musical tone at a pitch determined by the corresponding fret operating element and the sounding timing determined by the corresponding stringed operating element. When the arm is operated a CPU provides control to apply a choking effect to a musical tone for a sounding channel in which the musical tone is being sounded by raising the pitch of the musical tone by a predetermined amount.
U.S. Pat. No. 5,848,166 issued to Fisher et al on Dec. 8, 1998 discloses an audio tremolo producing system that uses a rotating horn as a tremolo producing device for mid and high frequency audio signals, and an electronic tremolo producing device that is capable of both phase and amplitude modulation for low frequency signals.
U.S. Pat. No. 3,240,859 issued to Rowe on Mar. 15, 1966 discloses a transistorized tremolo unit being mounted entirely on the musical instrument for tremolo regulation, adjustment and control off the musical instrument.
U.S. Pat. No. 5,121,669 issued to Iba et al on Jun. 16, 1992 discloses an electronic stringed instrument that employs a plurality of sensors or monitors for instrument performance. Preferred sensors or monitors include a detector for detecting that a string of the instrument is vibrated, an apparatus for evaluating string-vibration strength or a string touch, an apparatus for discriminating a fret operation position on a fingerboard or a fundamental frequency of a vibration of the vibrated string, a tremolo arm sensor, and a string-bending sensor. These performance input parameters are assigned to various control functions for musical tones generated by a sound source and/or various control functions for effects added to these musical tones by an effector. The function assignment is preferably programmable. In an operation, a music control apparatus controls the sound source and/or effector in response to a performance monitor so that musical tones for the strings can be distinguished from each other or effects for the musical tones can be distinguished from each other. Therefore, a performance with the stringed instrument by a player can be fully expressed.
U.S. Pat. No. 4,882,967 issued to Rose on Nov. 28, 1989 discloses an improved mechanical tremolo apparatus for stringed musical instruments. The improved tremolo apparatus comprises a tremolo means to which a plurality of strings of the musical instrument are adapted to be secured for movement therewith; a means for mounting the tremolo means on the stringed musical instrument for movement from a first position to a second position to simultaneously decrease the tension of the plurality of the strings, and for movement from the first position to a third position to simultaneously increase the tension of the plurality of strings; a means for moving the tremolo means from the first position towards the second position and for moving the tremolo means from the first position towards the third position; a means for biasing the tremolo means in a direction to return the tremolo means to the first position when the tremolo means is moved towards the second position; and, a stop member movable between an inactive position, at which it is out of engagement with the tremolo means, and an active position at which it is in engagement with the tremolo means when the latter is at its first position. The stop member and the tremolo means are constructed and arranged so that when the stop member is in its active position, it precludes movement of the tremolo means from the first position toward the third position but allows movement of the tremolo means from the first position toward the second position.
However, the above relater arts do not provide means for obtaining a tremolo effect for a string musical instrument with a “stop-tail”, that is for an instrument that does not have a factory equipped electronic or mechanical tremolo. The above related arts do not provide means for attaching a temporary and removable tremolo device to a string musical instrument that can use benefits of both mechanical and electronic tremolos.